Slide-carrier attachment for stereopticons



J. B. BAWFQQN SLIDE CARRIER ATTACHMENT FOR STEREOTICONS Filed June 11,1927 Patented Sept.4 17, 1929 PATENT ori-#ICE JACOB BELL BARR/QN, OFCALGARY, ALBERTA, CAADA SLIDE-CARRIER ATTACHMENT FOB STEREOPTICONSApplication led J'une 11, 1927. Serial No. 198,131.

This invention relates to improvements in stereopticon machines andparticularly to attachments therefor wherein lantern slides may bevariably projected, and an object of the invention is to provide adevice of this character which may be readily attached to a stereopticonmachine andn which a plurality of lantern slides may be moved over abeam of light as desired.v

A further object is to provide a device of this character which willproject an image on a screen in ysuch a manner that the scope of theimage is mechanically regulated.

A still further object is to provide an attachment of this type whichwill permit the upward and downward movement of the lantern slides at arate of speed determined by the operator and will also permit theselective control of any portion of the image projectcd on any portionof the screen. A distinct advantage in vthis is seen when it isconsidered that a continuous and uninterrupted projection may beeffected on the screen, of a lengthy narrative or series of images orany desired number of repetitions thereof, at the same time the heatfrom the source of light is so resisted as to practically eliminate thebreaking or cracking of the lantern slides from that source.

Yet a further object is to provide a device of this character which isconstructed of few l parts, which may be attached to -any type ofstereopticon or projector, and which may be placed on the market at alow cost.

With the foregoing and other objects in view, the invention consists ofthe arranger ment of 'parts hereinafter more fully described in detailin this specification.

In the drawings which form part of the same: j A

Figure 1 is a view of my improved device secured to the condenser holderof a Stereopvticon machina Figure 2 is a perspective view of theassembled device.

Figure 3 is a front elevation of the lantern slide holder hereinafterreferred to as the slide Figure 4 is a perspective view looking at therear of the main holder hereinafter referred to as the holden l Figure 5is a. sectional plan taken through the centre of the assembled device.

Referring now more particularly to the 'drawingsfin which my improveddevice is illustrated, A represents the attachments as a whole securedto the condenser holder B of the stereopticon machine. The attachment,generally speaking, comprises a holder 10 and a slide 11. The holder 10,as will be seen by referring to Figures 2 and 4, is formed withguideways 12 and 13 and a centrally disposed longitudinal opening 14.Operatively mounted on the front of the holder in bearings 15 and 16 andadjacent the bottom thereof is a spindle or shaft 17. This shaft isprovided with an operating button 18 and a pair of pinions 19 and 20,while at the rear of the holder are a pair of spindles 21 and 22provided with pinions'23 and 24 and operating buttons25 and 26.

The guideways 27 and 28, mounted on the rear of the holder 10, areadapted to retain therein shutter members 29 and 30, while the shuttermembers are designed to provided a variable opening 31 through which abeam of light is directed. Each of the shutters are provided with a rack32 and 33 which for purposes of adjustment is adapted to be engaged bythe pinions 23 and 24.

The slide 11 which in operation is moved upwardly and downwardly bv theoperator as may be desired comprises a flat rectangular plate, providedwith toothed racks 34 and 35. The central portion of the slide is formedwith a longitudinal opening 36, the sides of which are formed withgrooves or guideways 37 and 38 ada ted to receive and retain thereinlantern sli es which are indicated by the numeral39.

Adjacent the guideways |are a plurality of clips 40 of any convenientdesign adapted as particularly illustrated in Figure 3 to retain thelantern slides in the guideways of the slide 11.

By reverting to Figure 2 it will be seen that when the slide is inoperable position in the holder 10 the racks 34 and 35 will be en- A lgaged by the pinions 19 and 20k` l 18 which rotates the s aft 17,causing the pinions 19 and 20,'in engagementwith racks In operation thedevice is secured to the condenser holder B by means of the lugs 4l, thelanternslides are then placed in the guideways and the device is readyfor operation. According to desirability, the slide containing thelantern slides, as previously stated, may be moved upwardly anddownwardly. This is accomplished b turning the button 34and'35,to movethe slide 11 in the desired direction. The set screw 42in the bearing 15is adapted to exert pressure upon the shaft 17 and thus prevent theslide l1 from slipping, whether in or out of operation.

The shutters 29 and 3() forming an important feature of the inventionmay be readily moved upwardly or downwardly or at. variance with eachother according to necessity. From this it will be seen that the openingthrough which the source of light is projected may be regulated so as toinclude the entire lantern slide passing in front of it or any desiredportion thereof, thereby projecting any desired portion of acompletenarrative so intended on any desired portion of a screen orprojection surface.

From the foregoing description it will be seen that my vimproveddevicecan be secured to practically any type of stereopticon orprojector machine, and that the lantern slides, readily removable,may-be passed over the beam of light from the condenser at a rate ofspeed determined by the operator, and further, that the beam of lightmay be so focused as to include or exclude any portion of the lanternslide, which may be projected to any desired location on the screen,permitting at the. same time repetitions as frequently as desiredwithout replacing the lantern. slide or slides. y

Although means for manually operating the device are shown in theaccompanying drawings, it will be understood that means such as anelectric motor could be successfully employed. Y

As many changes could be made in the above construction, and many'apparently widely different embodiments of my invention within thescope ofthe claims, constructed without depart-ing from the' spirit orscope thereof, it is intended that all matter contained in theaccompanying specification vand accompanying drawings shall beinterpreted in an illustrative and not in a limiting sense.

lVhat I claim as my invention is:

1. A device of the character described in combination with astercopticon machine, comprising a holder member arranged with anopening, an adjustable shutter member on the holder mounted adjacentsaid opening adapted to vary the opening and location holder memberformed with a longitudinal opening adapted to retain glass slidestherein, guideways formed in the holder adapted to .i

guide the movement of the slide through the holder and over the openingcreated by the shutter member, and operating means on the blolderadapted to operate the shutter and the s 1 e.

2. 'A device ofy the character described com-l prising a holder memberformed with an opening therein, adjustable shutter members mountedadjacent said opening and a movable slide formed with a centrallongitudinal opening ada ted to register with the opening in the hol er,lips formed in the slide adjacent the central longitudinal openingadapted to support therein glass lantern slides, a plurality of springclips adjacent the longitudinal opening adapted to securely retain thelantern slides in the slide member, and operating means adapted tooperate the slide as desired upwardly and downwardly through the holderand over an opening created by the adjustable shutter members.

3. A slide carrier attachment for stereoptithe o ieratingmeanshassociated with the slide therein through'which a beam of light ispro- `fected, a slide member associatedl with the cons comprlsing 1ncomblnatlon, a holder member formed wlth an opening therein, ad-

